The grant project seeks to define aspects of the extracellular environment that influence or control the growth of single nerve cells. By using substrata of varying adhesiveness, the ability of several types of embryonic neurons to conform to printed patterns of such material will be investigated. Related studies employ cell surface marking agents in the attempt to elucidate the dynamics of cell surface materials in the axonal growth cone of such cells. Other studies deal with the distribution of collagen and basal lamina materials in embryonic salivary glands, lungs, and kidneys, at the time that those epithelial organs are undergoing morphogenesis. BIBLIOGRAPHIC REFERENCES: Localization of Actin Filaments in Internodal Cells of Characean Algae. A Scanning and Transmission Electron Microscope Study. J. Cell Biol. 68:264-276. (1976), Y. Kersey and Norman K. Wessells. Survival and Development in Culture of Dissociated Parasympathetic Neurons from Ciliary Ganglia. Devel. Biol. S. Helfand, G. Smith, and Norman K. Wessells. May 1976 (in press).